The present invention relates to the use, during a heating operation, of a power measurement to determine when a heating operation has been properly completed, and more particularly to predetermining various parameters of a heating system such that by measuring peak power delivered by an electric heater, relative to some other parameter of the system, the proper completion of a heating operation is determinable.
The present invention is applicable to many different types of heating functions, from industrial heating of metals or the like, to food preparation, soldering irons and the like. In many repetitive operations, it is desirable to insure repeatability without concentrated operator attention.
In the present application of the invention, without intending to be limited thereto, the invention is discussed in terms of a soldering function.
Cold solder joints have been a major source of problems in electrical and electronic systems since the inception of this industry. The problem with cold solder joints has been greatly increased with the advent of chips, since overheating to insure against a cold solder joint may very well damage or destroy expensive and delicate chips. Thus, a technician or operator, particularly one in a high production environment, is often walking a tightrope between underheating and overheating during a soldering operation, both conditions resulting in a defective component or board, some of these boards costing more than one thousand dollars.